This species can be easily distinguished from all other spiders.
Females may be 1/4 inch long and slightly less than 1/2 inch
wide. They have 6 pointed projections that are referred to as
spines. The carapace, legs, and venter are black, with some white
spots on the underside. The dorsum of the abdomen is typically
white with black spots and red spines, and some local specimens
may have yellow instead of white on the abdominal dorsum, and
may also have black spines instead of red. Some may be almost
entirely black dorsally and ventrally. Males are much smaller
than females; the male's color is usually white on the abdomen
with gray and white spots. The large abdominal spines are missing,
although there are 4 or 5 small humps on the posterior. The two
specimens pictured above are female.